1. Field of the Invention
The present invention relates to a cooling air blowing apparatus of a refrigerator, and more particularly, to a cooling air blowing apparatus of a refrigerator that is capable of improving an efficiency of a refrigerator by increasing air flow and reducing a noise.
2. Description of the Background Art
In general, a refrigerator includes a freezing chamber for keeping frozen items and a cooling chamber for keeping refrigerated food, and a freezing cycle is also provided therein to supply cooling air to the freezing chamber and the cooling chamber.
The refrigerator is increasingly having a large capacity and in order to keep foodstuffs in a fresh state for a long period, it is requisite to maintain an internal temperature to be uniform. For this purpose, a method is adopted that cooling air is discharged from several grill holes of the cooling chamber, for which cooling air passage tends to be lengthened and complicated to guide cooling air to each direction of the cooling chamber.
FIG. 1 is a side sectional view of a refrigerator in accordance with a conventional art, and FIG. 2 is a partial sectional view showing that an axial flow fan is mounted in the refrigerator in accordance with the conventional art.
The conventional refrigerator includes: a main body 104 having a certain space for storing foodstuffs and a door mounted to be opened and closed at a front side; a freezing chamber 106 formed at an upper side of the main body 104 and storing a frozen food; a cooling chamber 110 separated from the freezing chamber by a barrier 108 and formed at a lower portion of the main body 104 and storing a refrigerated food; a heat exchanger 112 mounted at a rear side of the freezing chamber 106 and providing cooling air through heat exchange with a refrigerant, and a cooling air blowing unit supplying cooling air generated while passing the heat exchanger 112 to the freezing chamber 106 and the cooling chamber 110.
The cooling air supply unit includes an axial flow fan 114 mounted at a rear side of the freezing chamber 106 and blowing cooling air in an axial direction of a direction that cooling air is introduced; a grill fan 118 having discharge holes 116 discharging cooling air blown by the axial flow fan 114 to the freezing chamber 106; a supply passage connected to a lower side of the grill fan 118 and supplying cooling air blown by the axial flow fan 114 to the cooling chamber 110; and a cooling air duct 132 connected to the supply passage 120 and formed at least one of at a rear side and at a side face of the cooling chamber 110 and having a plurality of cooling air discharge holes 122 discharging cooling air to the cooling chamber 110.
The axial flow fan 114 is fixed at a rotational shaft 126 of a driving motor 124, the driving motor 124 is fixed at a motor mount 128 formed inside the grill fan 118, and a shroud 130 is formed at a circumferential direction of the front side of the motor mount 128.
The supply passage 120 is formed between the shroud and the grill fan so as to be connected to a lower side of a branch passage 150 for distributing cooling air blown from the axial flow fan into the cooling chamber and the freezing chamber, and serves as a passage for supplying cooling air blown from the axial flow fan 114 to the cooling air duct 132.
At the barrier 108, a suction passage 134 is prepared through which cooling air which has completed a freezing operation of the freezing chamber 106 is sucked to the heat exchanger 112, and a suction barrier 136 is also prepared through which cooling air which has completed a cooling operation of the cooling chamber 110 is sucked to the heat exchanger 112.
FIG. 3 is a front view of the axial flow fan in accordance with the conventional art.
The conventional axial flow fan 114 includes a hub 152 connected to the rotational shaft 126 of the driving motor 124 and receiving a driving force of the driving motor 124, and a plurality of blades 154 installed at regular intervals at an outer circumferential face of the hub 152 and generating a blowing force.
The blade 154 is extended in a curved form having a certain curvature from the outer circumferential face of the hub 152. Typically, four blades are formed.
Typically, the axial flow fan 114 blows cooling air in a suction direction along the axial direction.
The operation of the refrigerator constructed as described above will now be explained.
When the axial flow fan 114 is rotated according to driving of the driving motor 124, cooling air which has passed the heat exchanger 112 is blown to the branch passage, discharged from the branch passage to the freezing chamber 106 through the discharge hole 116 of the grill fan 118 and also supplied to the supply passage 120.
The cooling air discharged to the freezing chamber 106 circulates in the freezing chamber 106 to perform a freezing operation and sucked to the heat exchanger 112 through the suction passage 134.
Cooling air introduced into the supply passage is supplied to the cooling air duct 132, discharged to the cooing chamber 110 through the plurality of discharge holes 122 formed at the cooling air duct 132, circulates in the cooling chamber 110 to perform a cooling operation, and sucked into the heat exchanger 112 through the suction passage 136.
However, the cooling air blowing apparatus of a refrigerator in accordance with the conventional art has the following problems.
That is, cooling air is blown in a suction direction along the axis direction from the axial flow fan. Thus, cooling air supplied to the freezing chamber is smoothly blown as the discharge hole of the grill fan is connected in the axial direction. But as for the cooling air supplied to the supply passage connected in the orthogonal direction in which cooling air flows through the axial flow fan, a flow resistance occurs, causing that the amount of cooling air supplied to the storage chamber is relatively small and thus a cooling operation is not smoothly performed.
Especially, as refrigerators are on the trend of becoming large, the supply passage for supplying cooling air is lengthened and complicated, so that a great amount of flow resistance occurs to flowing of the cooling air.
In order to circulate cooling air smoothly and quickly under the condition of the high flow resistance, the axial flow fan should have a large diameter or an RPM should be increased.
However, in case of enlarging the diameter of the axial flow fan, the size of the refrigerator is increased and a noise is accordingly generated. Meanwhile, in case of increasing the RPM, since the noise is increased, the quality of the refrigerator is degraded.
Especially, when the refrigerator is operated for a long period, when the heat exchanger is frosted, a noise becomes more loud while the air volume becomes small, resulting in that the freshness of the foodstuffs kept in the cooling chamber is degraded.
Therefore, an object of the present invention is to provide a cooling air blowing apparatus of a refrigerator that is capable of circulating cooling air smoothly and quickly even in a cooling air passage structure which is long and complicated by blowing cooling air in a suction direction along the axis direction and blowing cooling air in a radial direction of the direction in which cooling air is sucked.
Another object of the present invention is to provide a cooling air blowing apparatus of a refrigerator that is capable of reducing a noise by increasing an amount of cooling air supplied to a cooling chamber and a freezing chamber even without increasing a diameter of an axial flow fan or an RPM, and capable of increasing a blowing efficiency and improving a quality of a refrigerator.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a cooling air blowing apparatus of a refrigerator including: a driving motor fixed at a motor mount formed at a rear side of a freezing chamber; a blowing fan mounted at a rotational shaft of the driving motor and blowing cooling air in a suction direction along the axis direction and blowing cooling air in a suction direction along a radial direction, while being rotated as the driving motor is driven; and a shroud positioned in a circumferential direction of the blowing fan.
In the cooling air blowing apparatus of a refrigerator of the present invention, the blowing fan includes a hub fixed at the rotational shaft of the driving motor, axial flow fan blades formed at regular intervals in the circumferential direction of the hub and blowing cooling air in a suction direction along the axial direction; and a turbo blade formed extended at an outer end portion of the axial flow blade and blowing cooling air sucked in the axial direction by the axial flow blades, in a radial direction.
In the cooling air blowing apparatus of a refrigerator of the present invention, the axial flow blades are formed by 6xcx9c7 in number which are formed at regular intervals at an outer side of the hub.
In the cooling air blowing apparatus of a refrigerator of the present invention, the axial flow blade is formed as an axial flow fan type and formed in a curved face form having a certain radius of curvature and blows cooling air in the same direction as that of the cooling air sucked into the blowing fan.
In the cooling air blowing apparatus of a refrigerator of the present invention, the turbo blade is formed between blade tip and trailing edge of axial flow blade.
In the cooling air blowing apparatus of a refrigerator of the present invention, the turbo blade is formed extended along the curvature of the axial blade to form the same face with the axial flow blade.
In the cooling air blowing apparatus of a refrigerator of the present invention, the turbo blade is formed as a centrifugal turbo fan type and discharges cooling air in a suction direction along a radial direction to the blowing fan.
To achieve the above objects, there is further provided a cooing air blowing apparatus of a refrigerator including: a driving motor fixed at a motor mount formed at a rear side of a freezing chamber; a blowing fan mounted at a rotational shaft of the driving motor and blowing cooling air in a suction direction along the axial direction and blowing cooling air in a suction direction along a radial direction, while being rotated as the driving motor is driven; a shroud positioned in a circumferential direction of the blowing fan; and a guide unit formed at a front side of the shroud, guiding cooling air blown by axial flow blades to the freezing chamber and guiding cooling air blown by a turbo blade to a cooling chamber.
In the cooling air blowing apparatus of a refrigerator of the present invention, the guide unit includes: a guide plate extended as long as a certain width to a front side of the shroud and formed at a front side of the blowing fan; a guide hole formed at a front side of a guide plate and guiding cooling air blown by an axial flow blade to supply cooling air to freezing chamber; and a guide channel formed at a side of the guide plate and guiding cooling air blown by a turbo blade to supply cooling air to cooling chamber.
In the cooling air blowing apparatus of a refrigerator of the present invention, the guide hole has a diameter which is the same or larger than an outer diameter of the axial flow blade.
In the cooling air blowing apparatus of a refrigerator of the present invention, the guide channel is formed having the same width or larger than the width of the turbo blade.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.